Drawing 1678, the first one of the future Krematorium IV, two copies of which were to he built (the second being Krematorium V), was drawn in haste in order to try to deal with the catastrophic situation in which the camp found itself in August 1942. A typhus epidemic was raging and Bunkers 1 and 2 were regularly turning out batches of gassed bodies to be buried in the Birch Wood, a procedure that constituted a major health hazard at the height of summer. The urgency with which the drawing was produced can be seen in its unfinished appearance and by comparing the date on which it was checked and approved (15th September 1942) with the date on which the chimneys were ordered (20th August 1942), the former being much later than the latter.

The fact is that the building was merely the frame in which an eight-muffle cremation furnace was to he housed, the drawings of this already having been supplied by Prüfer, the chief engineer of Messrs Topf. The title “Einäscherungsanlage / Cremation installation” rather than “Krematorium” indicates that it was the act of incineration that had priority and that the planned facility would be of more summary design than Krematorien II and III.

Despite its apparent innocence as a sanitary instrument, there is a criminal element, linked with homicidal gassings, in the drawing. The essential parts of a crematorium are its furnace(s) and its morgue(s). Other ancillary rooms may go to complete this basic unit, such as coke store, laying out room, dissecting room and various others. In the arrangement of the premises, the only two rooms that are to be found in the immediate vicinity of the furnace room are those containing what is essential for its operation: coke from the coke store and corpses from the morgue. On Drawing 1678, the coke store is shown, but the morgue is not. The only room big enough to serve this purpose is the uncompleted room on the left. beyond the air lock. The complementary drawing 2036, despite the absence of a specific label, makes it clear that this is the only room that could fulfil this function. This room, a morgue by virtue of its position, has by definition to be cool, but the SS planned it to be fitted with a stove [symbol #], which would be absurd. The arrangement of the premises in a homicidal crematorium (one with a gas chamber) was in accordance with an inescapable logical sequence. For example, in the new crematorium at Dachau, there follow the undressing room, the gas chamber (labelled “Brausebad” / Shower bath"), the morgue and the furnace room. In Auschwitz Krematorium I, the room that served first as a morgue and then as a gas chamber was next to the furnace room. The most noticeable difference between the two types of use is the air temperature: a morgue needs to be cool or cold, while a gas chamber using Zyklon-B needs to be heated to 26° or 27° C to facilitate the diffusion of the hydrocyanic gas. The presence of a stove in the uncompleted room of drawing 1678 is a formal indication that it was used for gassing. The weakness of this criminal trace is that it stands alone. Its strength is that it exists: this symbol of a stove cannot he “rubbed out” or forgotten.

Drawing 1678 is connected with Bunkers 1 and 2. Instead of locating furnaces at the exits of their gas chambers as Prüfer had suggested in order to solve the problem of the mass graves, the SS preferred to bring the two functions (gassing and cremating) under the same roof. As evidence of this “affiliation”, the method of introducing Zyklon-B into the gas chambers in Krematorien IV and V was directly inspired by that used in Bunkers 1 and 2, the pellets containing the poison being poured through openings covered by wooden shutters, set high in the walls of the gas chamber and accessible only by means of a ladder.

Since Bunkers 1 and 2 were the only gas chambers in continuous operation in July-August 1942, the SS were willing to abandon them only in favour of two installations that could perform the same “work” much “better": cremation installations IV and V. subsequently known as Krematorien IV and V.